The technical field of this invention relates to devices for the dispensing of non-solid, viscous materials.
Cartridges for storing and dispensing viscous materials such as resins, sealing compositions, dental compositions, or insulation compositions are known in the art. Such cartridges generally comprise an outer casing containing at one end, an end piece which attaches to an application nozzle and at the other end, a rear thrust wall designed to slide toward the end piece and force the viscous material out of the nozzle. This sliding of the rear thrust wall is brought about by a piston which is generally an integral part of a manual operating device, usually in the form of a gun equipped with a rack or friction advance mechanism.
Some viscous products consist of several viscous components which must be mixed, in given proportions, only at the time of application. It is known in the art to store the viscous components in multiple containers inside cartridges in such a way that the advancing rear Thrust wall will force the components through a single mixing nozzle whereby the components become mixed at the time of application.
U.S. Pat. No. 5,339,992 to Barthomeuf et al discloses a cartridge comprising an outer casing and an inner casing. Each casing holds a viscous component of a final product. The cartridge has a front end piece for receiving an application nozzle and a rear thrust wall which drives the components forward and through the nozzle when it is advanced.
The closest prior art known to the inventor are U.S. Pat Nos. 5,161,715, 5,184,757, and 5,242,082 to Giannuzzi. These patents disclose a double-barreled gun designed to inject a two-component epoxy composition. The gun contains two parallel barrels, each containing a foil pack containing viscous components of the final epoxy composition. The gun contains two front end pieces which are adapted to send the components into a mixing nozzle. The gun contains two pistons for urging the foil packs forward. As the foil packs are urged forward, cutting elements in the forward end of each barrel slit the foil packs and allow for the discharge of the stored components.
U.S. Pat. No. 3,767,085 to Cannon et al, U.S. Pat. No. 5,722,829 to Wilcox et al, and U. S. Pat. No. 5,875,928 to Muller et al are similar to each other in that each of these references discloses a double-barreled cartridge capable of receiving two parallel containers containing viscous materials which should be mixed only at the time of application. Each container empties into a front end piece which passes the viscous components to a mixing nozzle. Each container has a rear thrust wall which may be forced forward to expel the contents of the container into the front end piece.
Thus, cartridges and guns for these cartridges for use with viscous components which must be kept separate from each other are well known in the art. One problem which exists is the incompatibility of the cartridge of one manufacturer with the gun of another manufacturer or even the gun of the same manufacturer with a different size cartridge. Thus, a multiplicity of guns and cartridges are on the market, only a few of which are compatible.
The inventor recognized this problem and solved it by providing a cartridge which fits common caulking guns and which holds a container made up of a plurality of material chambers which hold viscous ingredients which should be kept separate until the time of application. The cartridge and containers are designed for a single use, and are constructed of recyclable materials. The chambers may have a variety of ratios of the several components.
The cartridge contains a tubular casing, a forward end cap having an orifice capable of snugly holding a piece capable of coupling with a conventional mixing nozzle, and a rear thrust wall capable of being urged forward by the piston of a conventional caulking gun.
The container is made up of multiple collapsible chambers containing closed rear ends, closed side edges, at least one edge being in common for at least a portion of the length of a side, and a forward end in which the forward edges of the chambers are sealed to a forward end piece. The collapsible chambers may be sealed bags made of sturdy plastic or expandable and compressible chambers having accordion configurations. Each forward end piece has a body portion, a shoulder portion, and a neck portion. When in position in the cartridge, the multiple body portions of the end piece will form a circle which will abut with the cartridge, the shoulder portions will abut with the end cap, and the neck portion will snugly fit through an orifice in the end cap to engage a mixing nozzle.